Belfast International and Cardiff airports may be put up for sale by their Spanish owner.
Barcelona-based infrastructure firm Abertis said it was reviewing its 29-strong airport division which owns Belfast International and Cardiff airports, and operates Luton Airport under a long-term contract.
Abertis acquired Belfast International at Aldergrove, which deals with some 12 million passengers a year, through subsidiary TBI in 1996.
A spokesman for Abertis, which also has airports in Mexico, America and Sweden, said: "We have started a process of reviewing our airport division, including the possibility of a future sale of the division."
He said Abertis, which is listed on the Spanish stock exchange and also manages toll roads and telecommunications infrastructure, had appointed Citi and AZ Capital to look into the future of the division.
The Spanish group, which made profits of €720m (£472m) in 2011, has seen passenger traffic hit by the economic woes of the country. The possible sale comes after the recent lucrative sell-off of Stansted and Edinburgh airports by Heathrow Airport Holdings – formally BAA – in the wake of a Competition Commission ruling.
The Welsh government has already said it is looking at buying Cardiff airport, and it is thought to be close to a deal. The airport has seen passenger numbers halve since 2007, falling to one million last year.
The potential sale of Luton comes after a dispute between Abertis and the town's council.
Luton Borough Council, which owns the airport, threatened to end Abertis' contract in a dispute over its vision for developing the airport.